Dental

A *dental* sound is a consonant sound that is made when your tongue touches the back of your top row of teeth. Read these words in English--*hands* and *pants*. The "ds" and "ts" parts are dentals, because the tip of your
tongue is touching the back of your top teeth. Those two sounds are spelled "z" and "c" in the Chinese romanization. The reason those sounds are hard for English speakers is because in English we only have those sounds on the ends of words, but in Chinese they come at the beginning of words.